In a principal aspect, the present invention relates to an apparatus for determining whether the spark plug of an internal combustion engine is properly generating an ignition spark or electrical discharge so as to ignite vaporized fuel.
When servicing an internal combustion engine, a mechanic often finds it necessary to determine whether the spark plugs for the engine are providing an appropriate electrical discharge or spark in each of the cylinders of the engine. A determination of ignition spark enables the mechanic to diagnose whether engine operation is defective due to a faulty ignition system or alternatively, due to a faulty fuel delivery system. That is, by determining whether appropriate electrical charge or spark is delivered via the spark plug of the internal combustion engine, the mechanic quickly and easily determines that the ignition system is working properly. Thus, if the spark is generated, then there may be a defect associated with the fuel delivery system. Alternatively, if there is no spark, then the ignition system is not working properly.
There are at least two devices known which are used to check the viability of the ignition system. These devices are made available by SandG Tool Aid Corporation of Newark, N.J. Their product numbers are No. 23900 and No. 23920 and are depicted in FIGS. 1 and 2, respectively. Product No. 23900 is identified as an inline ignition spark checker and includes a male contact or probe connected in a circuit with a light indicator. The male probe projects from one end of the device. An inline boot or lead wire for connection to the head of a spark plug is provided at the opposite end of the device. Product No. 23920 is an alternative construction wherein the boot or lead wire is a 90xc2x0 boot designed for use in situations where the inline boot will not be useful or workable. Thus, in order to check the spark at each and every cylinder of a multi-cylinder internal combustion engine, it may be necessary to use both tools, depending upon the orientation and position of the spark plug in the engine block. A mechanic may necessarily need to switch back and forth between tools in order to check the ignition system associated with each of the cylinders of an internal combustion engine. Such switching back and forth, as well as the cost of two tools to perform the same function, has inspired the development of the present invention.
Briefly, the present invention comprises an apparatus or mechanic""s tool for evaluating the ignition system, and more particularly, the delivery of electrical current via the ignition system to a spark plug of an internal combustion engine. The tool has universal application in that the tool utilizes either an inline boot for connection to the head of the spark plug or an angled, i.e. 90xc2x0 boot, depending upon the requisite need and accessibility of the spark plug associated with the internal combustion engine that is being serviced.
Thus, the tool includes a lead wire having an inline female boot at one end and a 90xc2x0 connection boot at its opposite end. The tool further includes a generally cylindrical body member with male connectors screw-threaded to each end of the body member. Internally, the body member is hollow and includes an indicator light in series with the male connectors projecting from the opposite ends of the body member into the hollow cylindrical body member. A spring inside the body member is interposed between the light and the male connectors to insure electrical continuity for the device. A lead wire boot may be connected to either of the male connectors projecting from the body member and may also be connected at either end to the head of a spark plug. Thus, the single tool disclosed may be utilized for inline or angle connection of the tool to the head of a spark plug and thereby provide a continuity check of the ignition system.
Thus, it is an object of the invention to provide an improved ignition system diagnostic tool.
It is a further object of the invention to provide an ignition system diagnostic tool which may be utilized for checking an electrical spark via a spark plug in an ignition system regardless of the orientation or position of the head of the spark plug in the engine block.
It is a further object of the present invention to provide a diagnostic tool for ignition systems which is inexpensive, rugged, easy to use, has broad application for various types of engines and spark plugs associated with such engines, and which is lightweight and inexpensive.
These and other objects, advantages and features of the invention will be set forth in the detailed description as follows.